Open GL Periods for "after month end" consolidation entries

So we have started using Oracle FSG's for our consolidations.  In doing so, we are making JE's for eliminations.  Typically these JE's come well after all of our "regular" operating units close their books and we close the monthly GL period.  However, we are not comfortable doing this because of the risk of someone accidentally and/or intentionally creating a JE while we reopen this past period.  We go through the obvious checks to assure that no JE's were made while open but would like to hear how other companies handle this.
Is there anyway to just open the GL period for these specific Companies (they are balancing segments not truly legal entities since these are simply used for elimination entries)?  I don't believe this is possible so we have also considered a complete other ledger that is for those eliminating entry balancing segments.